This invention relates to methods of operating turbochargers and to a unique turbine housing design for a turbocharger.
Turbochargers are well known in the prior art and conventionally utilize a turbine wheel and a compressor impeller mounted on a unitary or common shaft, carried within respective housings for same. The turbine housing includes a gas inlet and a gas outlet wherein there is provided, in the typical case, an internal scroll configuration as is well known to the art.
Exhaust gases from an engine are directed to the turbine housing to drive the turbine wheel which in turn causes rotation of the compressor impeller which compresses ambient air and/or air-fuel mixture to supply same in the compressed state to the intake manifold of the engine. The gas outlet is connected to an exhaust gas discharge system through which the spent exhaust gases are passed. In cases where it is necessary to prevent overcompression of the air or air-fuel supply mixture being fed to the engine, it becomes necessary to bypass the turbine and to wastegate the excess gases to the exhaust gas system. The prior art has typically provided for bypassing of the unwanted exhaust gases prior to introduction thereof into the turbine of the turbocharger which necessarily has dictated that valving arrangements be positioned in proximity to the turbine housing or to be integral therewith. In so doing, the acutator being located on either the turbine or compressor housing limits the location of the device within the engine compartment, or alternatively, requires special mounting brackets and the like, which severely curtails placement of the device in the engine compartment because of space and size limitations.
This invention relates to a method of operating turbochargers and more specifically the turbine thereof, at its highest level of efficiency and to bypass exhaust gases once same have been fed through the turbine housing and more specifically the internal scroll thereof and to provide a turbine housing which has the capability of being adapted for use with or without a wastegate mechanism. Where a wastegate mechanism is utilized in conjunction with the turbocharger, a modular design wastegate may be used which may be selectively and conveniently associated with the turbine housing of the invention so that the turbocharger unit may be utilized in a variety of modes within an engine compartment in various mounting positions. The central location of the bypass gas exit port or wastegate port in a central manner allows for symmetrical placement of the device within the engine compartment to thereby provide for left or right mounting in conjunction with other of the apparatus making up the total assemblage.
The turbine housing of the invention with the integral wastegate provision at the terminus of the internal scroll of the turbine housing, as opposed to the inlet, thereof allows for operation of the turbine at higher efficiency and further permits use of the turbine housing without a wastegate should the need arise by simple capping off of the exit port.